First time poster here, couldn't find my specific issue, so here goes. I have a 1983 F-150 with a 4.9 L 6 cyl. I have replaced the mechanical fuel pump, bypassed the front fuel tank and only use the rear tank. I have had the carb rebuilt, replaced the belts, spark plugs, wires, distributor cap, fuel filter, fuel line from rear tank to new pump, the electronic unit (not a mechanic, can't remember the computer box thingamajig), starter, alternator, and master cylinder. She runs great, until I get below 3/4 full in fuel. I suspect the fuel pickup but I don't know and I am not a mechanic, just some guy who enjoys tinkering with his old beater that his wife says is an eyesore! Am I correct in my assumption? I don't want to attempt that unless it's necessary. Please help!

 

When the engine sputters, and you pull in to a gas station, how many gallons does it take to FILL the tank? Does it always take about the same?



When did this symptom appear? When were all those parts replaced in relation to the appearance of this symptom? Did YOU do all the work to the truck, or did you have someone else do it? Where are you getting these parts, and what brand is each one?

 

It always takes the same amount of gas each time I refill the tank when it goes below 3/4 full. I didn't notice this issue for a long time because I never kept more than 1/2 a tank and it ran rough. I started replacing parts because they were all original, got everything from Autozone. The only work I didn't do myself was the carb rebuild, and that's because "A man's got to know his limitations". After replacing the fuel line, I pulled it off the feed from the rear tank and stuck it in a full gas can. Worked fine.

 

You didn't say how many gallons.

You're not doing yourself ANY favors by buying from the zone. Their parts are the cheapest garbage there is, and they're generally FAR more expensive in the long run than buying high-quality parts up front. Shop Amazon, eBay, RockAuto, TeamFordParts.com, 1stFordParts.com, FordPartsGiant.com, your local Ford dealer, and local parts stores (like Advance & Parts+Plus) for MotorCraft parts, or at least US-made parts whenever possible.

Your gas can test suggests the fault IS in the tank. This & the NEXT several pics & their captions show the easy way to access the tank:

 

Steve83,

Sorry, 19 gallons is the tank size, and it's usually between 5-6 gallons each time I need to refill. So stay away from the zone, but Advance is okay? Gotcha. Also, you say it's the tank, not the pickup? Thanks again for all your help!! Much appreciated.

 

The pickup IS in the tank.............